A Hot Mars-sized Exoplanet Transiting an M Dwarf
Abstract We validate the planetary nature of an ultra-short-period planet orbiting the M dwarf KOI-4777. We use a combination of space-based photometry from Kepler, high-precision, near-infrared Doppler spectroscopy from the Habitable-zone Planet Finder, and adaptive optics imaging to characterize this system. KOI-4777.01 is a Mars-sized exoplanet ( R p = 0.51 ± 0.03 R ⊕ ) orbiting the host star every 0.412 days (∼9.9 hr). This is the smallest validated ultra-short period planet known and we see no evidence for additional massive companions using our HPF RVs. We constrain the upper 3 σ mass to M p < 0.34 M ⊕ by assuming the planet is less dense than iron. Obtaining a mass measurement for KOI-4777.01 is beyond current instrumental capabilities.
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Award ID(s):
Publication Date:
NSF-PAR ID:
10344426
Journal Name:
The Astronomical Journal
Volume:
163
Issue:
1
Page Range or eLocation-ID:
3
ISSN:
0004-6256
National Science Foundation
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